Various techniques and devices are known for administering medicaments through the skin, particularly for veterinary use. One example of such a technique is described in U.S. Pat. No. 4,026,290, which suggests attachment of a device to the ears or tail of the animal for applying motion sickness mitigators, anti-migraine compounds, analgesics, anthelmintics, antiprotozoal compounds and systemic insecticides, miticide and acaricides.
Transdermal drug delivery in veterinary applications is discussed in an article entitled "Topical Drug Delivery to Cattle and Sheep" by Ian H. Pitman and Susan J. Rostas, in Journal of Pharmaceutical Sciences, Vol. 70, No. 11, November, 1981, pp. 1181-1193 and in an article by the same authors entitled "A Comparison of Frozen and Reconstituted Cattle and Human Skin as Barriers to Drug Penetration", in Journal of Pharmaceutical Sciences, Vol. 71, No. 4, April, 1982, pp 427-430. Transdermal drug delivery has been proposed for administering prophylactic medicaments in veterinary contexts but, to the best of the knowledge of the inventors, has not had any practical application of significance in veterinary practice.
Growth regulators and growth promoters, here collectively termed "growth promoters", are commonly used in veterinary applications and are often applied using implants which cannot be conveniently removed prior to slaughter. Hormones for synchronization in mammals are generally administered vaginally, a technique which requires skill and involves potential damage to the animal and could result in infertility.